Landing gear includes shock-absorbers that present various chambers that are separated by various walls or separations presenting throttling orifices and that are filled with hydraulic fluid and with gas under pressure. When landing gear is in a deployed position, a shock-absorber is generally in a substantially vertical position such that, as a result of the difference in density, the gas and the hydraulic fluid in the shock-absorber are to be found respectively at the top and at the bottom thereof.
Nevertheless, when the landing gear is in a folded position in a wheel bay of the aircraft, the hydraulic fluid and the gas progressively spread out in the various chambers of the shock-absorber by passing through the throttling orifices. In particular, the gas occupies part of a chamber known as the oil chamber that is situated beneath the separation, referred to as the “diaphragm”, that subdivides the inside of the shock-absorber. When the landing gear is moved into its deployed position prior to landing, the hydraulic fluid and the gas under pressure migrate so as to return progressively to their initial state, by passing through the throttling orifices. Nevertheless, this return to the initial state can take quite a long time, such that under certain circumstances, it can happen that the aircraft lands before the hydraulic fluid has had time to fill completely the oil chamber situated under the diaphragm.